Friction draft gear



Dec. A. F. STUEBING FRICTION DRAFT GEAR Filed Jan. 25 1926 5 Sheets-Sheet l Dec. 15, 1931. A. F.8TUEBING 1,836,294

FRICTION DRAFT GEAR Filed Jan. 25, 1926 3 Sheets-Sheet 2 6 @355 z l I I Q Z ,W I fla /W7 dzewtzbzzew Dec. 15, 1931. STUEVBING 1,836,294

FRICTION DRAFT GEAR Filed 1926 3 Sheets-Sheet 3 Patented Dec. 15, 1931 UNITED. STATES PATENT OFFICE ALBERT F. STUEIBING, OF NEW YORK, N. Y., ASSIGNOR TO THE BRADFORD lIATEN'lS CORPORATION, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE rRIo'rion nnAr'r GEAR Application filed January 25, 1926. Seria1'No.'83,698}

My. invention relates to friction draft gears employed in connecting railway cars and particularly to such a gear which includes two groups of friction plates movable longitudinally and respectively in re" sponse to pulling and pushing strains, the plates of each group being'alternated with the plates of the other group, that is, the plates being in so-called intercalated arrangement.

The invention has a number of advantageous characteristics among which are the provision of a spreading device, preferably a wedging device, which is subject to draft strains and is disposed in the midst of the plates of both groups and which presses outwardly upon the plates on each sidethereof in response to draft strains, and a constricting device, also preferably a wedging device, operating in conjunction with the spreadingdevice, and also subject to and operable by draft strains and laterally embracing both groups of plates and pressing inwardly-uponthe plates in response to draft strains; ap-

z plication springs, located abreast, and. a spacer, preferably floating draft strain transmitting member interposed between these springs and the constricting device and through which member said springs operate upon said constricting device to cause it, to press inwardly upon .the plates; release springs operating upon one group of plates to effect relatively releasing movement of said groups ofplatesupon reduction in. draft strain, a spacer between the springs, and a spanner crossing the spacer and interposed between the release springs and the group of plates afiected thereby; the provision: of strengthening formations'upon portions of some of the plates that are projected'beyond the paths of movmentof plates contiguous thereto, such strengthening formations being desirably. afforded by thickening or crowning the plates thus projected; center column serving as a spacer between-the two release springs which'd'esirablyenclose the application springs and operating to limit the maXimumeXtent of relative movement of the two g'roups'of plates in response jto, draft strains, this center column having a portion longitudinally of the gear on both sides of this u floating--member; an arrangement of the plates of both groups in similar directions oblique to the axis of the gear to produce motion retarding friction as the two groups of plates are moved longitudinally of the gear in response to draft strains; the provision'of constricting mechanism resisting the transverse movements of the obliquely ar ranged plates in response to draft strains; the provision of application spring mechanism for transmitting draft strains to the constricting mechanism whereby the resisting action of the constricting mechanism increasesand is augmented by frictional resist- .ance as thedraft strain increases; the employment of wedging blocks through which said application spring mechanism functions; andv the arrangement of the center column to withstand oversolid impact to protect the gear. H

The invention has other useful features that will be more fully described in conned-- tion with the accompanying drawings in which Fig. 1 is a plan view of a friction draft 7 gear constructed in accordance with the preferred embodiment of the invention, parts being shown in section, this figure being taken generally on line1-1 ofFigaQ; Fig.2

is a sectional elevation on line 22-of Fig. 1:

Fig. 3 is a siderview of part of the gear, partially in section, showing otherfeatures of construction not illustrated in Fig. 2;. Fig. 4 is a plan view of part of the gear, with parts shown 'in section. showing parts not illustrated in Fig. 1; Fig. 5 is a sectional view on line 5+5 of Fig. 1:; Fig. 6 is a sectional view on line 66 of Fig. '1; Fig. a perspective view illustrating the'center column andthe floating member that isin actuating relation to the constricting device, these parts being shown in separated relation; Fig. 8 is a perspective view of the spanner which crosses the center column and is interposed between the release springs and the plates; Fig. 9 is a perspective view illustrating one friction plate of each of the two groups of plates; and Fig. 10 is a perspective view showing the parts of the constricting device in separated relation.

The draft gear of my invention may include any suitable form of coupler and yoke and maybe associated with any suitable form of draft sills.

The coupler stem 1, illustrated in the drawings, is provided with a key 2 extending transversely therethrough and snugly fitting the same to travel therewith. I have illustrated a yoke which is inclusive of a looped strap 8 arranged in a vertical plane and having a forked outer end in the sides of which horizontal slots 4 are formed, these slots being longer than the width of the key 2 that passes therethrough, this key pulling upon the yoke when the gear is subject to pulling strains and moving inwardly in the slots 4 when the gear is subject to buffing or pushing strains. The key 2 passes through hori- Zontal slots 5 formed in the draft or center sills 6, the key occupying a middle position in these slots when the draft gear is normal or idle and being moved outwardly in these slots when the gear is subject to pulling strain and inwardly in these slots when the gear is subject to pushing or bufling strain. Bridge pieces 7 and 9 underlie the draft or center sills and are in supporting relation to the coupler stem and yoke. The inner end of the stem and the outer end of the yoke are supported by means of the key 2 and the bottom sides of the slots 5 on which this key slides. The yoke surrounds an outer follower 10 and an inner follower 11. The outward movement of the outer follower is limited by draft lugs 12 secured upon the inner faces of the center sills and the inner movement of the inner follower is limited by draft lugs 13, similarly secured. hen the gear is subject to pushing or buffing strains, the outer follower 10 is moved inwardly by the inner end of the coupler stemand the inner follower 11 is held from inward movement by the draft lugs 13, the inner end of the yoke being desirably interposed between the follower 11 and the draft lugs 13. When the gear is subject to pulling strains, the inner follower 11 is moved outwardly by the rear end of the coupler yoke and the outer follower 10 is held against outward movement by the draft lugs 12. The movements of the followers longitudinally of the gear are resisted by the mechanism of my invention.

The motion retarding mechanism is inclusive of one group of friction plates 14 and a second group of friction plates 15, these plates being movable transversely thereof and of the gear, both groups of plates being movable longitudinally of the plates and of the gear in response to pulling and pushing draft strains, respectively. The plates of each group are alternated with the plates of the other group and have frictional engagement therewith. A spreading device, subject to draft strains, is disposed in the midst of the plates of both groups and presses out- 7 wardly upon the plates on each side thereof in response to draft strains. This spreading device is desirably in the form of an inwardly tapering wedge portion 16 which constitutes the inner end portion of the center column 5 member 17 receiving end thrusts in both directions, which is, preferably, integrally formed with the outer follower 10. "he spreading device is desirably also inclusive of washer plates 18 of uniform thickness, between which the wedge 16 is disposed, these washer plates being especially replaceable to compensate for wear. Said column member supports the elements 14, 15 and 18. The

washer plates also function similarly to plates 9- 14 and are included in the same group therewith. The plates 14 and 18 are formed with notches 19 and 20 in their bottom and top sides, these notches receiving the ribs 21 and 22 which are formed upon the inner faces of a the horizontal flanges 23 and 24 of the center column structure. Said ribs are disposed transversely of these plates and the gear and serve to cause these plates to move with the center column and the follower 10 that is a 3.

part of the center column structure. The wedge 16 causes the washer plates 18 to converge inwardly. These washer plates cause the plates 15, contacting therewith, also to converge inwardly. The plates 15 cause the plates 14:, next to and on the outer sides thereof, to converge inwardly. These plates 14 cause the plates 15, next to and on the outer sides thereof, to converge inwardly, and so on, the wedge 16 thus causing the plates on one side thereof to slope inwardly and similarly toward the axis of the gear and the plates on the other side thereof also to slope inwardly and similarly toward the axis of the gear. The plates 15 are engaged by the follower 11 and are moved outwardly thereby in response to pulling strains and are stationary when the draft gear is subject to pushing strains. As these plates 15 are slightly oblique with respect to the axis of the gear, they are pressed upon outwardly and laterally by the action of the spreading element 16 and the plates let and 18 that are similarly oblique to the axis of the gear.

As the two groups'of plates are relatively moved longitudinally of the gear, frictional engagement between the plates of one group and the plates of the other group occurs, the friction producing pressure between the plates of the two groups obviously increasduced, the construction being suchthat release of motion "retarding frictional engagement between theplates of the two groups is quickly effectedwhen 'the draft strain is reduced. Outward transverse movement of the plates on each side of the gear aXis is resisted by the springs 25. These springs desirably also constitute application springs, being arranged to press inwardly upon the plates with increasing force as the draft strains increase. The friction between the plates of the two groups is thus not onlyincreased in response to relative movement of the two groups due to increasing draft strains, but is'also further increased by the increasing spring pressure of the springs 25 as the draft strains increase. ferred embodiment of the invention, the springs 25 are bottomed upon the follower 10 at their outer ends and engage a floating draft strain transmitting'member 26 at their inner ends. The center column member 17 is interposed between the springs and the floating member 26 crosses the column member '17 and preferably surrounds the same, the wedging portion :16 projecting inwardly beyond the member 26. The springs 25 press upon the floating member 26 and the floating member 26 presses upon the inwardly taper ing friction wedge blocks 27. These wedge blocks frietionally engage the friction wedge portions 28 that constitute; outer continuations of the inner follower 11. The friction plates are desirably. arranged in vertical planes as arealso the wedging elements 27 and 28. The structure is strengthened by connecting the wedging elements 28 by means of the webs 29 which form with the wedging elements 28 andthe follower 11, itself, an open ended boX receiving the inner and-the major portions of the plates and blocks.

The elements 27 and 28, in conjunction with the springs 25, constitute a constrictingdevice which laterally embraces the .plates and functions to take part in effecting increasing frictional engagement between the parts is the draft strain increases,as explained. the draft strain increases, the wedge blocks 27 will move apart, the springs 25 mcreasin l 0 osin this relative movement of these blocks. The relative movement of the two groups offriction plates longitudinally of the gear is desirably opposed by the center column member 17 and its wedging por-' tion 16, the inner end of this wedging portion engaging the follower 11 when the limit of relative longitudinal movement ofthe two groups of plates has been reached in response In the preto withstand oversolid imin response to draft strains, the plates 15 are projected forwardly of the plates 14 and 18. In being thus projected, the plates 15 press upon a floating member, preferably the spanner 30 and the spanner presses upon the inner ends of the release springs 31 whose outer ends are bottomed upon the follower 10. These release'springs are under a minimum degree of compression whenthe gear is released and then press, with minimum pressure, upon the spanner 30 and through the spanner upon the plates. The compression of the springs 31is increased according to the extent to which the plates 15 are projected forwardly beyond the plates 14 and 18. lVhen the draft strains are reduced, the release springs 31 function. to restore the two groups of plates to their normal or idle relative positions in which the forward'ends of the plates of both groups are substantially flush. The releasingpower ofthe springs 31 is stored therein when the gearis being put under compression to be in readiness to nally of or with respect to said column member. The spanner is desirably bifurcated at its ends so as to have exten ded engagement with the inner ends of the release springs 31 between .which the column member 17 is disposed and also with the forward ends'of the plates 15.

- Assembling bolts 33 pass through the cars 34 of the H shaped center column, the floating member 26 and thecorner portions 35 Pl l of the wedge block actuator 11, 28. These bolts. serve to holdthe gear parts together beforeinstalla tion and afterremoval of the gear. q l i While the wedge block actuator 11, 28is shown at the inner end of the gear and the follower portion 10 of the H shaped center column is shown at thefront end of the gear, the invention is not to be thus limited, the spring and'frictionjmechanismof the gear obviously operating similarly with draft strainsj applied at either end. f

In the preferred embodiment of theinven tionfithe notches 19and 20' are not quite filled, lengthwise of the gear, bythe ribs 21 and 22 on the center column, an arrangelid 'mitthe spring inent affording suflicient lost motion to permechanism to initially take the impact without then producng friction. In releasing, the first movement of the gear is the sliding movement, as a unit, of the friction plates 14, 15 and 18, the wedge blocks 27, the wedge block actuator 11, 28, and the floating members 26 and 30, this initial sliding release movement being very limited and continuing until the lost motion permitted by the clearance between the ribs 21 and 22 and the notches 19 and 20 is absorbed. When this clearance is taken up and the friction plates 14 and 18 are brought in firm engagement with said ribs 21 and 22, there will be a slightimpact which will tend to start relative movement between the friction plates of the two groups. As the movement continues, the friction wedge blocks 27 will move toward each other, due to the inclination of the friction plates to the gear axis, and the friction set up between these blocks 27 and the wedge elements 28 of the follower 11 will reduce the wedging pressure and facilitate release. The application springs 25, during the release movement, also overcomes the frictional resistance between wedge blocks 27 and the adjacent plates 14. This will reduce the force transmitted from the application springs to the wedge blocks and thus decrease the wedging pressure on the friction plates during release. In case the force of the release springs is not sufficient to overcome the friction of plates 15 during release, the application springs Will move the floating member 26, the wedge blocks 27, and the follower 11 inwardly until the floating member 26 comes in contact with the front ends of plates 15. Pressure on the wedge blocks is consequently then relieved, both the applicatron springs and release springs functioning to restore plates 15 to their normal relative positions.

I employ the term center column in the sense that it is rigid and receives end thrusts in both directions due to draft strains.

Changes may be made without departing from the invention.

Having thus described my invention, I claim:

1. A friction draft gear including a flanged central column having a tapered portion; intercalated friction plates supported by the flanged formation of the central column and bearing against said tapered portion of the column; means for setting up pressure on said plates; and means for returning the plates to release position.

2. A friction draft gear including a central H-shaped column having a tapered port-ion and having its web portion arranged longitudinally of the gear; relatively longitudinally movable intercalated friction plates supported by column flanges on each side of the column Web and bearing against said tapered portion; spring means on each side of the column; a transverse floating member cooperating with the relatively movable friction plates passing through and movable longitudinally of the gear within an opening formed through the web, said floating member receiving pressure of said spring means, said column serving to take over-solid impact and limit the movement of the friction plates, and means for setting up pressure on said plates.

3. A friction draft gear including a central column; two groups of relatively longitudinally movable intercalated friction plates mounted obliquely on both sides of the col- 1111111 and supported thereby; means for setting up pressure on the plates and yieldingly resisting relative motion of the plates; and means for returning the plates to release position.

4. A friction draft gear including a cen tral column and having a wedge supported by the column; groups of relatively longitudinally movable intercalated friction plates supported by said column 011 each side of the wedge; means for setting up pressure on the outside plates and yieldingly resisting relative motion of the plates; and means for returning the plates to release position.

5. A friction draft gear including a center column; two groups of relatively longitudinally movable intercalated friction plates supported on the sides thereof; means for setting up pressure on the plates; release spring means; and a release member between the release spring means and one group of plates and extending through the column and transmitting pressure from the spring means to the plates.

6. In a draft gear, a longitudinal central column having a follower plate at one end adapted to receive spring means, said column being formed with an opening therethrough, adapted to receive a floating member in engagement with said spring means and subject tostrains imposed upon the gear, the end of said column opposite to said follower bearing friction means co-operating with said floating member under compressive strains.

In Witness whereof, I hereunto subscribe my name.

ALBERT F. STUEBING.

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